Marinette is the main female protagonist in Miraculous Ladybug. She's a young girl with a kind heart and a secret identity as a superhero. As for Camemburt, it's likely a character made up for this particular fanfic idea. Maybe the author wanted to create a new love interest for Marinette, so they came up with Camemburt. But again, this is just speculation without actually reading the story.
Marinette could use her wits. If she's tied up, she might be able to find a sharp object nearby to cut the ropes. For example, if she's in a room with some old furniture, there could be a nail or a broken piece of wood that she can use.
Another reaction could be that Marinette pretends to cooperate with Adrien at first. By doing this, she can buy time and look for an opportunity to escape or get help. She might act as if she is okay with what is happening while secretly planning her next move, like leaving a clue for someone to find her or finding a way to disable Adrien temporarily.
Diana in 'my 600 pound life diana story' is the main focus of the story. Since it's part of 'my 600 pound life', she's probably someone who has been living with extreme obesity. The story may detail her personal battles, such as trying to lose weight, dealing with health problems that come with being 600 pounds, and her relationships with others while in this situation.
Concubine Dai was a popular author. Her novels were based on princesses and were very popular among readers. One of the recommended novels was "Your Majesty Can't (H)", which was a novel about ancient princesses, palace fights, and harem. It told the poignant and pure love story between the main characters, Ran Yuan and Ji Sheng. In addition, there was another recommended novel,"He Under the Yellow Robe". This was an ancient novel about a 1v1 between a man and a woman. It told the story of the Cold Palace Princess Chu Han becoming the new emperor and the eunuch leader Rong Qin. These novels were all written by Concubine Di. They had wonderful plots and excellent writing, so they were worth reading.
She might befriend Iron Man first. Since he's into technology and Marinette is quite creative when it comes to making things. They could bond over creating new gadgets or improving existing ones.
Marinette can react by standing up for herself. She might confront Chloe directly and tell her that her actions are wrong. This shows Marinette's strong character.
It could be Bruce Wayne himself. Marinette might admire his business acumen and his philanthropy work in Gotham. His mysterious persona as Batman could also be very appealing to her, especially if she has a taste for adventure and mystery.